President Barack Obama visits the cell where Nelson Mandela, an anti-apartheid activist, was once jailed on Robben Island, June 30, 2013. Paying homage to the 94-year-old former South-African president, who was critically ill in hospital, Obama stared into the stark cell where Mandela spent two thirds of his 27 years in jail.

President Obama tonight offered a deeply personal reflection on the life and legacy of Nelson Mandela, a man he described as "one of the most influential, courageous and profoundly good human beings that any of us will share time with on this Earth."

"He no longer belongs to us; he belongs to the ages," Obama said.

"Through his fierce dignity and unbending will to sacrifice his own freedom for the freedom of others, Madiba transformed South Africa and moved all of us. His journey from a prisoner to a president embodied the promise that human beings and countries can change for the better," he said in a brief statement in the White House Briefing Room. "His commitment to transfer power and reconcile with those who jailed him set an example that all humanity should aspire to, whether in the lives of nations or in our own personal lives."

The president has long described Mandela as one of his personal heroes and an early inspiration for his political career.

"My very first political action -- the first thing I ever did that involved an issue or a policy or politics was a protest against apartheid. I would study his words and his writings. The day he was released from prison it gave me a sense of what human beings can do when they're guided by their hopes and not by their fears," he said.

"Like so many around the globe, I cannot fully imagine my own life without the example that Nelson Mandela set. And so long as I live, I will do what I can to learn from him," he said.

Obama met Mandela only once in person, during a spontaneous meeting in Washington in 2005. It was a brief visit at the Four Seasons Hotel in Washington –- that almost didn't happen. At the time, Mandela was exhausted after delivering a speech to the NAACP and meeting with President George W. Bush and he wasn't taking meetings with freshmen senators.

Obama and his aides took a chance and pressed to see him. The then senator arrived at the Georgetown hotel in the front seat of an aide's Volkswagen Passat. The meeting was short, but the iconic photograph of their visit, taken by Obama's aide David Katz, lives on. That photograph, the only one of their meeting, hangs in the West Wing of the White House.

A year later, when Obama visited South Africa, Mandela was too sick to see the senator. Instead, Obama visited Robben Island on that 2006 trip and stood in the small prison cell where Mandela was held for 18 of his 27 years in captivity.

It was a trip that Obama repeated this past June, this time with his family. But as president he would never have the chance to talk to Mandela.

"We will not likely see the likes of Nelson Mandela again. So it falls to us as best we can to forward the example that he set: to make decisions guided not by hate, but by love; to never discount the difference that one person can make; to strive for a future that is worthy of his sacrifice," Obama said today.

"For now, let us pause and give thanks for the fact that Nelson Mandela lived -- a man who took history in his hands, and bent the arc of the moral universe toward justice. May God Bless his memory and keep him in peace."